* durante muchos años = for many years, for years to come, for many years to come, over many years, for years and years (and years).

* durante mucho tiempo = long [longer -comp., longest -sup.], for generations, long-time [longtime], for a long time to come, for long periods of time, for a long period of time, lastingly, for a very long time, for many long hours, for a long time, in ages (and ages and ages).

* durante muchos años= for many years, for years to come, for many years to come, over many years, for years and years (and years).

* durante mucho tiempo= long [longer -comp., longest -sup.], for generations, long-time [longtime], for a long time to come, for long periods of time, for a long period of time, lastingly, for a very long time, for many long hours, for a long time, in ages (and ages and ages).